feat: implement XML attachment file naming functionality (backport #253)

eu_einvoice/european_e_invoice/custom/sales_invoice.py

@@ -17,6 +17,8 @@
 from frappe import _
 from frappe.core.doctype.file.utils import find_file_by_url
 from frappe.core.utils import html2text
+from frappe.model.naming import parse_naming_series
+from frappe.utils import cstr
 from frappe.utils.data import date_diff, flt, getdate, to_markdown
 
 from eu_einvoice.common_codes import CommonCodeRetriever
@@ -45,8 +47,10 @@
 
 @frappe.whitelist()
 def download_xrechnung(invoice_id: str):
-	frappe.local.response.filename = f"{invoice_id}.xml"
-	frappe.local.response.filecontent = get_einvoice(invoice_id)
+	invoice = frappe.get_doc("Sales Invoice", invoice_id)
+	base_name = get_xml_attachment_file_base_name(invoice)
+	frappe.local.response.filecontent = get_einvoice(invoice)
+	frappe.local.response.filename = f"{base_name}.xml"
 	frappe.local.response.type = "download"
 
 
@@ -906,7 +910,8 @@ def _attach_xml_file(doc: SalesInvoice, xml_content: bytes, field_name: str | No
 			)
 			return
 
-	file_name = f"{doc.name}.xml".replace("/", "-")
+	base_name = get_xml_attachment_file_base_name(doc)
+	file_name = f"{base_name}.xml"
 
 	# Create new File document
 	file_doc = frappe.new_doc("File")
@@ -1129,3 +1134,40 @@ def attach_xml_to_pdf(invoice_id: str, pdf_data: bytes) -> bytes:
 
 	xml_bytes = get_einvoice(invoice_id)
 	return attach_xml(pdf_data, xml_bytes, level)
+
+
+def get_xml_attachment_file_base_name(doc, *, pattern: str | None = None) -> str:
+	"""Filename stem (no `.xml`) for the downloadable XML.
+
+	Uses *pattern* when given, otherwise reads *Auto name format for XML file*
+	from **E Invoice Settings**. Falls back to `doc.name` when the pattern is
+	empty or fails to resolve. Result is sanitized via `_get_safe_file_name`
+	(same rules as **File** attachments).
+	"""
+	if pattern is None:
+		pattern = frappe.get_single_value("E Invoice Settings", "auto_name_format_for_xml_file")
+	pattern = cstr(pattern).strip()
+	if pattern:
+		try:
+			base = parse_naming_series(pattern, doc=doc, number_generator=_no_series_counter).strip()
+		except Exception:
+			frappe.log_error(
+				title=_("E Invoice XML file name pattern failed"),
+				message=frappe.get_traceback(),
+				reference_doctype=doc.doctype,
+				reference_name=doc.name,
+			)
+			base = ""
+		if base:
+			return _get_safe_file_name(base)
+	return _get_safe_file_name(doc.name)
+
+
+def _get_safe_file_name(file_name: str) -> str:
+	"""Local-only; mirrors ``get_safe_file_name`` in Frappe v17+ file utils."""
+	return re.sub(r"[/\\%?#]", "_", file_name)
+
+
+def _no_series_counter(_key: str, _digits: int) -> str:
+	"""Disable the series counter so XML naming has no DB side effects."""
+	return ""

eu_einvoice/european_e_invoice/custom/test_sales_invoice.py

@@ -0,0 +1,58 @@
+from unittest.mock import patch
+
+import frappe
+from frappe.tests.utils import FrappeTestCase
+
+from eu_einvoice.european_e_invoice.custom.sales_invoice import (
+	get_xml_attachment_file_base_name,
+)
+
+
+class TestXmlAttachmentNaming(FrappeTestCase):
+	def test_auto_name_format_from_e_invoice_settings(self):
+		doc = frappe._dict(name="SINV-00001", po_no="PO-42", doctype="Sales Invoice")
+		field = "auto_name_format_for_xml_file"
+		pattern = "XMLSTEM.-.{po_no}"
+		real_gsv = frappe.get_single_value
+
+		def get_single_value(doctype, fname, cache=True):
+			if doctype == "E Invoice Settings" and fname == field:
+				return pattern
+			return real_gsv(doctype, fname, cache=cache)
+
+		with patch.object(frappe, "get_single_value", side_effect=get_single_value):
+			self.assertEqual(get_xml_attachment_file_base_name(doc), "XMLSTEM-PO-42")
+
+	def test_empty_or_whitespace_uses_doc_name(self):
+		doc = frappe._dict(name="SINV/00001", doctype="Sales Invoice")
+		self.assertEqual(get_xml_attachment_file_base_name(doc, pattern=""), "SINV_00001")
+		self.assertEqual(get_xml_attachment_file_base_name(doc, pattern="   "), "SINV_00001")
+
+	def test_dot_separated_pattern_with_field(self):
+		doc = frappe._dict(name="SINV-00001", po_no="PO-1", doctype="Sales Invoice")
+		base = get_xml_attachment_file_base_name(doc, pattern="EXAMPLE.-.{po_no}")
+		self.assertEqual(base, "EXAMPLE-PO-1")
+
+	def test_dot_separated_inv_field_end(self):
+		doc = frappe._dict(name="SINV-00001", po_no="X-9", doctype="Sales Invoice")
+		base = get_xml_attachment_file_base_name(doc, pattern="INV.-.{po_no}.-.END")
+		self.assertEqual(base, "INV-X-9-END")
+
+	def test_leading_hashes_stripped_per_part_avoids_series_counter(self):
+		doc = frappe._dict(name="SINV-00001", po_no="PO-1", doctype="Sales Invoice")
+		base = get_xml_attachment_file_base_name(doc, pattern="EXAMPLE.-.{po_no}.#####")
+		self.assertEqual(base, "EXAMPLE-PO-1")
+
+	def test_hash_in_literal_sanitized_like_file_utils(self):
+		doc = frappe._dict(name="SINV-00001", doctype="Sales Invoice")
+		base = get_xml_attachment_file_base_name(doc, pattern="INV#X")
+		self.assertEqual(base, "INV_X")
+
+	def test_only_hash_segments_falls_back_to_doc_name(self):
+		doc = frappe._dict(name="SINV-00001", doctype="Sales Invoice")
+		self.assertEqual(get_xml_attachment_file_base_name(doc, pattern="#####"), "SINV-00001")
+
+	def test_slash_in_resolved_base_is_sanitized(self):
+		doc = frappe._dict(name="SINV-00001", po_no="A/B", doctype="Sales Invoice")
+		base = get_xml_attachment_file_base_name(doc, pattern="{po_no}")
+		self.assertEqual(base, "A_B")

eu_einvoice/european_e_invoice/doctype/e_invoice_settings/e_invoice_settings.json

@@ -13,6 +13,8 @@
   "error_action_on_submit",
   "sales_invoice_number_field",
   "section_break_yldr",
+  "auto_name_format_for_xml_file",
+  "column_break_vlzj",
   "auto_attach_xml",
   "attach_field_for_xml_file"
  ],
@@ -53,8 +55,20 @@
    "options": "\nWarning Message\nError Message"
   },
   {
+   "bold": 1,
    "fieldname": "section_break_yldr",
-   "fieldtype": "Section Break"
+   "fieldtype": "Section Break",
+   "label": "XML Settings"
+  },
+  {
+   "description": "Pattern for the <b>file name</b> of the XML.  <b>.xml</b> is appended automatically. Leave <b>empty</b> to use the document <b>name</b> (Sales Invoice ID). In case of an error, the document <b>name</b> is used as fallback.\n<br><br>Segments use a <b>dot</b> (<b>.</b>) between literal text and dynamic parts. Example:<br><b>EXAMPLE-.MM.-.{po_no}.-.YYYY</b><ul><li><b>Dates</b>: <b>DD</b>, <b>MM</b>, <b>YYYY</b>, <b>YY</b>, <b>WW</b>, <b>timestamp</b></li><li><b>Fields</b>: <b>Sales Invoice</b> field names in braces, e.g. <b>{po_no}</b></li><li>Other segments are treated as literal text.</li></ul>",
+   "fieldname": "auto_name_format_for_xml_file",
+   "fieldtype": "Data",
+   "label": "Auto Name Format for XML File"
+  },
+  {
+   "fieldname": "column_break_vlzj",
+   "fieldtype": "Column Break"
   },
   {
    "default": "0",
@@ -80,7 +94,7 @@
  "index_web_pages_for_search": 1,
  "issingle": 1,
  "links": [],
- "modified": "2026-02-06 17:52:09.990716",
+ "modified": "2026-05-08 11:55:24.180676",
  "modified_by": "Administrator",
  "module": "European e-Invoice",
  "name": "E Invoice Settings",
@@ -101,4 +115,4 @@
  "sort_field": "creation",
  "sort_order": "DESC",
  "states": []
-}
+}

eu_einvoice/european_e_invoice/doctype/e_invoice_settings/e_invoice_settings.py

@@ -18,6 +18,7 @@ class EInvoiceSettings(Document):
 
 		attach_field_for_xml_file: DF.Autocomplete | None
 		auto_attach_xml: DF.Check
+		auto_name_format_for_xml_file: DF.Data | None
 		error_action_on_save: DF.Literal["", "Warning Message", "Error Message"]
 		error_action_on_submit: DF.Literal["", "Warning Message", "Error Message"]
 		sales_invoice_number_field: DF.Autocomplete | None